The present invention is directed to a sensing assembly for determining the moisture content of the material being dried in a domestic laundry drying apparatus.
Dryer sensor assemblies are known in the art, such as for example that disclosed in U.S. Pat. No. 3,593,571, assigned to the assignee of the present invention. That sensor assembly incorporates a bridging-type sensor assembly for use in a domestic laundry dryer wherein a pair of sensing elements having leg portions extend through an insulating mounting base and through a bulkhead of a drying chamber for engagement by resilient clips which secure the sensing assembly onto the bulkhead. In the arrangement disclosed in that patent, the sensing elements are mounted on a separate mounting post and are secured in place by clips engaging on the opposite side of the bulkhead. The sensor operates to detect moisture by sensing a current flow between the pair of sensor elements when bridged by wet or damp material.
In an axial flow dryer, where the heated air is directed into the interior of the rotating drum through a rear bulkhead and is directed out of the drum at a front side of the drum, the fabric being dried within the drum is naturally carried toward the front of the drum by the axial air flow. Thus, the mounting of the sensor at the rear bulkhead becomes less effective, particularly in small fabric loads in that there may be occasions where long time periods exist wherein the fabric does not engage the rear bulkhead. Such an occurrence would provide an erroneous reading if the moisture sensor were secured to the rear bulkhead.
Additionally, the use of a separate mounting base member and securing clips requires a labor and material intensive assembly of multiple parts.
Therefore, it would be an improvement in the art if there were provided a sensing assembly for determining the moisture content of material within the dryer which is positioned in a location to be continuously in engagement with the material being dried and which would incorporate a reduced number of assembly pieces to provide a more efficient and economical assembly of the sensor apparatus.